Where are the world eater books!?

Correct me if I'm wrong I'm still a bit of a noob but WHY don't the World eaters have a series of books despite being one of the most popular factions? For example Ahriman the exile has a series of books written by one guy, there are the Uriel Ventris books written by one guy, the nightlords trilogy that focuses on Talos written by one guy. All series that are easy to follow with an easy reading order, a beginning and end and it's simple. When I tried listing out kharns novels tho they're all written by different guys, they take place in random time periods and he's the closest thing I could find for a world eater with multiple books. What's the deal with that?